Hépatites B et C en pédiatrie : analyse rétrospective dans un centre universitaire suisse

Introduction Généralité Le virus de l'hépatite B fait partie de la famille des hepadnavirus, son génome est fait d'un double brin d'ADN. Les marqueurs d'une infection par ce virus sont les antigènes « s » (HBsAg) qui sont des antigènes des surfaces, les antigènes « c » (HBcAg) et les antigènes « e » (HBeAg) qui sont tous deux des antigènes des « core protein » qui contiennent le génome du virus (1). Le virus se trouve dans le sang, la salive, le sperme, les sécrétions vaginales ; il existe un risque important de transmission lors de contact avec ces fluides corporels infectés (2). Dans les pays où la prévalence est plus élevée, la transmission se fait généralement dans les premières années de vie dont 50% résultent d'une transmission verticale, c'est-à-dire que le virus est transmis par la mère durant la grossesse ou l'accouchement (3) alors que dans les pays où l'hépatite B est moins fréquente, l'infection survient plutôt chez les jeunes adultes, à travers les relations sexuelles ou les injections intraveineuses de drogues (4). Le virus des hépatites B est une cause importante de morbidité et de mortalité à travers le monde. En effet, l'infection chronique par ce virus reste relativement fréquente et peut causer des insuffisances hépatiques, des cirrhoses et même des carcinomes hépatocellulaires (5)

Quantum simulation of an extra dimension

We present a general strategy to simulate a D+1-dimensional quantum system using a D-dimensional one. We analyze in detail a feasible implementation of our scheme using optical lattice technology. The simplest non-trivial realization of a fourth dimension corresponds to the creation of a bivolume geometry. We also propose single- and many-particle experimental signatures to detect the effects of the extra dimension.Comment: 5 pages, 3 figures, revtex style;v2 minor changes, references adde

Carbon dioxide emissions of Antarctic tourism

The increase of tourism to the Antarctic continent may entail not only local but also global environmental impacts. These latter impacts, which are mainly caused by transport, have been generally ignored. As a result, there is a lack of data on the global impacts of Antarctic tourism in terms of energy consumption and carbon dioxide emissions. This paper presents and applies a methodology for quantifying CO2 emissions, both for the Antarctic vessel fleet as a whole and per passenger (both per trip and per day). The results indicate that the average tourist trip to Antarctica results in 5.44 t of CO2 emissions per passenger, or 0.49 t per passenger and day. Approximately 70% of these emissions are attributable to cruising and 30% to flying, which highlights the global environmental relevance of local transport for this type of touris

Cadastral data integration through Linked Data

Ponencias, comunicaciones y pósters presentados en el 17th AGILE Conference on Geographic Information Science "Connecting a Digital Europe through Location and Place", celebrado en la Universitat Jaume I del 3 al 6 de junio de 2014.Cadastral data is one of the more important types of geospatial data. Taking into account the importance of these data, several international bodies have worked for creating a standardised model for land administration. However, in spite of existing efforts, there are several open issues for the development of a harmonized vision of cadastral data. Taking into account this scenario, Linked Open Data may allow addressing some of these challenges, by proposing best practices for exposing, sharing, and integrating data on the Web. This paper shows a use case where two cadastral information sources are semantically integrated according to Linked Data principles. These sources belong to different Colombian cadastral producers and are characterized by different heterogeneity issues. Herein, we describe an implementation of Linked Data principles in the cadastral domain using LADM standard (ISO 19152) and GeoSPARQL. Besides, our original data are enriched with different dataset of Linked Data cloud (LinkedGeoData and GeoNames)

Simulation of gauge transformations on systems of ultracold atoms

We show that gauge transformations can be simulated on systems of ultracold atoms. We discuss observables that are invariant under these gauge transformations and compute them using a tensor network ansatz that escapes the phase problem. We determine that the Mott-insulator-to-superfluid critical point is monotonically shifted as the induced magnetic flux increases. This result is stable against the inclusion of a small amount of entanglement in the variational ansatz.Comment: 14 pages, 6 figure

The Role of Bulge Formation in the Homogenization of Stellar Populations at z∼2z\sim2 as revealed by Internal Color Dispersion in CANDELS

We use data from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey to study how the spatial variation in the stellar populations of galaxies relate to the formation of galaxies at $1.5 < z < 3.5$. We use the Internal Color Dispersion (ICD), measured between the rest-frame UV and optical bands, which is sensitive to age (and dust attenuation) variations in stellar populations. The ICD shows a relation with the stellar masses and morphologies of the galaxies. Galaxies with the largest variation in their stellar populations as evidenced by high ICD have disk-dominated morphologies (with S\'{e}rsic indexes $< 2$) and stellar masses between $10 < \mathrm{Log~M/ M_\odot}< 11$. There is a marked decrease in the ICD as the stellar mass and/or the S\'ersic index increases. By studying the relations between the ICD and other galaxy properties including sizes, total colors, star-formation rate, and dust attenuation, we conclude that the largest variations in stellar populations occur in galaxies where the light from newly, high star-forming clumps contrasts older stellar disk populations. This phase reaches a peak for galaxies only with a specific stellar mass range, $10 < \mathrm{Log~M/ M_\odot} < 11$, and prior to the formation of a substantial bulge/spheroid. In contrast, galaxies at higher or lower stellar masses, and/or higher S\'{e}rsic index ($n > 2$) show reduced ICD values, implying a greater homogeneity of their stellar populations. This indicates that if a galaxy is to have both a quiescent bulge along with a star forming disk, typical of Hubble Sequence galaxies, this is most common for stellar masses $10 < \mathrm{Log~M/M_\odot} < 11$ and when the bulge component remains relatively small ($n<2$).Comment: 15 pages, 14 figure